Each high availability solution has an associated cost. The cost for the solution must be compared to the benefit achieved for your business. When asked about a high availability solution, most customers will say that they want continuous availability with zero downtime. While this is technically possible, the cost of the protection offered by the solution may be too great.

The basic question behind how much resource should be given to a high availability solution is “What is the cost of an outage?” Backup sites, backup systems, backup copies of the application data have a cost, and an associated benefit for that cost. Until the actual cost of each unit of downtime is known, a true value cannot be assigned to the value of the additional benefit of the high availability solution to the customer.

Solution cost is the total cost of ownership which includes the initial cost to procure and deploy the solution, the ongoing costs to use the solution, and any cost/performance impacts. Cost is typically predicated on a thorough business impact analysis. The values are:
  • Cost is not a factor.
  • Cost has slight bearing on decision.
  • Based on outage analysis, the solution cost must be contained within some budget.
  • Cost is a significant factor in the decision.
  • Unwilling or unable to spend anything on availability solution.